This is single player Tetris, to be played from within Rift. Start the game with the command "/tetris" and follow the instructions on the screen.
While playing Tetris, no other keybinds will be responsive. If something comes up and you need access to your keys, just press "M" to minimize Tetris, you can continue your game later by typing "/tetris" again.
You can place the window wherever you want by click-and-drag.
Keywords: game minigame tetris single_player inception